import math


class Person:
    def __init__(self, name, age, sex):
        self.name = name
        self.age = age
        self.sex = sex

    def work1(self):
        print(f'{self.name}，{self.age}岁，{self.sex}，上山去砍柴')

    def work2(self):
        print(f'{self.name}，{self.age}岁，{self.sex}，开车去东北')

    def work3(self):
        print(f'{self.name}，{self.age}岁，{self.sex}，最爱大鸡腿')


p1 = Person('小明', 10, '男')
p1.work1()
p1.work2()
p1.work3()
p2 = Person('老李', 90, '男')
p2.work1()
p2.work2()
p2.work3()


class yuan:
    PI = math.pi

    def __init__(self, r):
        self.r = r

    def C(self):
        print(2 * yuan.PI * self.r)

    def S(self):
        print(yuan.PI * self.r * self.r)


o = yuan(3)
o.C()
o.S()
